NUTRIENTS IN RUMINANT NUTRITION

Nutrients

Nutrition is the series of processes by which an animal takes in and assimilates feed components for promoting growth, milk, or fiber production and replacing worn or injured tissues.

Water

71 % of the fat-free animal body. Free access to good-quality water. Acts as a solvent as most of our

enzymes are water soluble and need water to get dispersed.

Blood is composed mostly of water. Involved with the transport of waste

products in the urine.

Water Sources

Drinking water: free choice Water also from feeds: this water is not

chemically bond to feed. Dry feedstuffs have 9 % to 13 % free

water. Silage has 65 % to 75 % free water, 20

lb of corn silage @ 65 % water =13 lb of water consumed.

Water Sources

Metabolic water: water that is chemically bound to the feed and is released when the feed is broken down into nutrients.

Generally oxidative reactions.

Water Losses

Through urine, feces, lungs, skin, milk. Kidney uses lots of water (concentration-

dilution). High protein diet increases water losses;

high urea. increases urinary excretions. High in mineral salts increases urine. High fiber diets increase urine. Increase in food consumption increases

urine.

Water Losses

Water loss in feces varies; Sheep dry feces Cattle wet feces

Fecal water content reflects feed water content.

Evaporative water losses varies with heat, humidity and wind

Lactation: 100 lb milk has 87 lb of water

Water Quality

Affects water and feed consumption < 2,500 mg/l total dissolved solids (TDS) Depending on solids could tolerate

15,000 mg/l Toxicity may show up before palatability

reduces intake: nitrates, fluorine, other heavy metals

Water Quality

100 to 200 ppm nitrates toxic 1 g/l sulfate may causes diarrhea Palatability: problems from

microorganisms, algae, protozoa, hydrocarbons, pesticides, chemicals

Water Quality

Common minerals in water: chloride, sodium, calcium, magnesium, sulfates, bicarbonate

Mineral present depend on soil type and water source.

1% salt max for cattle and sheep Water as a source of minerals, yes ?

30% of NaCl; 15% Ca; 7% Mg; 32% Su

Average daily intake, cattle

Calf 51 5-6 Calf 93 9-10 Cattle (yearling) 350 23-30 Beef cattle 450-600 30-40 Dairy cow 545-730 38-100 Cattle on pasture 545-730 20-40

BW, kg L / day

Average daily intake, sheep

Lamb 9 1.5-2.5 Lamb 23 2-3.5 Sheep on pasture 60-90 4-8 Sheep (feedlot) 60-90 5-10

BW, kg L / day